


Inappropriate Sibling Relationships.

by xyChaoticFox



Series: SnK & smut is life xD [7]
Category: Shingeki no Kyojin | Attack on Titan
Genre: BL, Boy x boy, Don't Like Don't Read, Eren just wants some love, Incest, It's gross, Levi is mean, M/M, Mild Language, Mild Smut, Now a two shot with smut, One Shot, Serves him right, Sibling AU, Yaoi, You Have Been Warned, biting kink, he gets more than he expected, whatever!
Language: English
Status: Completed
Published: 2016-03-09
Updated: 2016-03-13
Packaged: 2018-05-25 18:53:38
Rating: Mature
Warnings: Underage
Chapters: 2
Words: 4,237
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/6206596
Author URL: https://archiveofourown.org/users/xyChaoticFox/pseuds/xyChaoticFox
Summary: <blockquote class="userstuff">
              <p>Eren needs comforting and runs to his big brother, who was dealing with a...little problem before he got disturbed.</p><p>[UPDATED: Added an alternative ending.]</p>
            </blockquote>





	1. Chapter 1

**Author's Note:**

> As always, English is not my native language and this is not beta'd. Please excuse any errors and feel free to correct me. Constructive criticism is appreciated! 
> 
> Please Enjoy this! :D
> 
> WARNING: Homophobes get out of here, like, now!
> 
> Disclaimer: I do not own the characters.
> 
> ◈Please don't be shy and talk to me. ◈

 

-

-

-

Sweat slowly form at the back of his neck; cool against his skin but wettiing the tips of his longer strands of hair. He swallows, adam's apple bobbing and his throat dry. The clock on his bedside is the only light, besides his phone, in the dark room and it flickers when it hits a new hour. 22:00. It's still early but normal for him to be in bed; student life was hard work and exhausting. He bites his lip, shifting his knees beneath the thin navy bedsheet. Waves hit him at the worst times, his hormones impatient and not receiving any relief due to his busy schedule. He is already fairly  aroused and unbearably hot when someone softly knocks against his door. His hand pauses at his waistband and he wants to throw a fit.

"What?"

"Levi? You busy?" It's his younger brother.

"Yes."

"Can I come in?"

"No, idiot." 

He hears a childish whine and a thump against his door, clearly recognizing it as Eren's head. He rolls his eyes and sits back against the headrest. He whistles and the door opens almost instantly, a mop of brown locks popping up from behind it. Eren tiptoes inside, closing the door behind him.

"It's dark." He mutters.

"No shit, sherlock. That's what happens at night."

Eren snorted, "You can leave a light on until you actually decide to sleep."

Levi sighs, "What do you want?" 

Eren stops at the side of his bed, looking almost hesitant before he ran a hand through his hair. He isn't wearing a shirt, Levi notes, his sculpted muscles showing faintly everytime the curtain moved and a moonbeam lit up the room. Eren is leaner than Levi, shoulders and chest narrow where Levi's is broader and more defined. Puberty was treating him well though; he was taller than Levi now. 

"Well?" 

"Can...I stay?" 

"Here? In my room?"

"Yeah."

"No."

"Leviii."

"Jesus, Eren. Now, really?"

"Why not?"

"You're 16, loser."

"So, old man?"

Levi ignored the comment this time, "So, 16 year old guys don't climb into 21-year old -or any-guy's bed."

"You're my brother, so shut up." Eren crosses his arms and the elder ignores the flexing lumps of muscle.

"Exactly my point."

"Don't be a dick," Eren's voice lowers, "You know I can't...when it's so close."

Levi inwardly sighed again, "Yeah, just get in." 

He reluctantly agreed and moved the covers, signalling Eren to get in. It reminded him of when they were little and Eren had nightmares. He often came running to Levi and slept closely cuddled undernearth his arm and chest. But now wasn't the time to repeat that; he could understand the sad thing but awkward cuddles were not needed.

"Just stay on your side." Levi slumped back into the bed.

"Like I want to be on your side." Eren tugged the covers.

"Fucking child." Levi unlocked his phone, checking his emails.

"Thought you wanted to sleep, asshole." 

"You go to sleep, you have school tomorrow." 

"Ah donf caaae." Eren muttered into a pillow.

Levi ignored him, sending a quick reply to a friend before tucking the device away. He turned onto his side, eyes blanky staring at the dark shadows which fell here and there. He tried to shift, knees rubbing together again. Levi would never jerk off with his brother in his bed or even his room for that matter. The only option was to remain quiet and hope it goes away. 

Eren was tossing, shifting and pulling the covers in multiple directions. Levi turned, not comfortable and slowly getting very irritated. Suddenly Eren's naked back brushed against him and his ass against Levi's prominant problem. He felt Eren's muscles contract and tense, the boy quickly sitting up and getting distance between them.

"What the hell!" he blushed, eyes wide.

"Fuck, I told you to stay back." Levi hissed.

"You could've told me you had a hard on! Not cool, man!" 

"Shut your mouth, dad's going to hear!" 

"So!"

"I swear to God, you little punk," Levi speedily sat up, "One more shout out of you and all your porn is history. I covered for you once but I'll easily tell him where it is!"

Eren glared at him, "I hate you." 

"Then get out of my bed."

"No, just keep the dick in your pants." 

Eren wiggled into bed and formed a little ball, pulling the covers over his head much like he did when he was smaller. Levi counted to ten before sliding back and muttering to himself.

 

\--

 

"Are you awake?" 

"No." Levi grumbled.

He heard a deep exhale, "What time is it?" 

"00:03." 

A short silence. 

"Levi?" 

"What?" 

"Can't sleep?"

"Do you think I'll be talking to you if I could?" 

Another silence.

"Levi?" 

"What, Eren?"

"Are you..still, you know?"

"Go to sleep." Levi snapped.

Levi could almost hear the gears turning inside Eren's head, the bed shifting short after.

"Levi, are you still a virgin?" 

"Are you sick, Eren?" 

"No! I was just asking since.. yeah, we were on the topic."

"We weren't."

"You know what I mean."

Levi didn't answer. 

"Soo...are you?" 

Levi rolled onto his back, just like Eren had moments ago, "You don't want to know."

"I do."

"Then no, Eren, no virgin." 

"Oh."

"You?"

"Eh..virgin."

"Knew it." 

"Jerk." Eren slapped Levi's shoulder.

Levi smirked.

"Levi?"

"That's my name."

"Are you gay?"

Levi froze, throat constricting and heart skipping a beat. They were talking for what seemed like the first time in ages and he wondered if he should lie.

"Yes." He didn't.

"Oh." 

Levi waited for the outburst, but what followed he was not prepared for. 

"I think I'm gay too." 

Levi choked on his saliva, Eren turning to look at him and pat his back when he sat back up for what seemed like the hundreth time this night.

"Wh-How?" 

"Girls don't turn me on, that type of shit. I might be asexual but I doubt that. I mean, I jerk off and the porn you know about."

"But the porn was straight." 

"Yup..I'm confused. But I think I'm gay."

Levi started to laugh, ah, how arrogant his little brother was. 

"Don't laugh!" 

" _You_ are not gay, Eren." Levi said in between chortles.

"And why the hell do you decide that?" 

Levi stopped laughing, serious in a split second. His movements were too fast and Eren was pinned before he knew it, Levi's strong thighs hugging his and his face so close their noses brushed. 

"Cause you freaked out about your brother's dick."

Levi's cool breath ghosted over Eren's blushing face and he stammered, shaking his head. Levi scoffed, shaking his as well before shifting to get off. Eren grabbed the back of his neck, yanking him back with a dizzying force. The boy was clumsy, his lips uncertain as they moved and completely off pace. Levi pushed against his shoulder, breaking away and keeping Eren against the pillow. Eren eyed him with gleaming eyes, breathing heavily and expecting him to yell and hit him for being so twisted. All Levi did was tease him but Eren just had to fuck it all up. 

"If you want to kiss someone, fucking know how to do it." 

Levi pressed his mouth against Eren's, moving slowly but urgently and urging the other to move. Slowly the brunette responded, fingers twisting into Levi's hair and his lips catching on to the pace. Levi's teeth caught onto his bottom lip, nipping and drawing it into his mouth to suck at the wounded flesh. Levi's tongue traced his lip once more before delving deep into Eren's mouth and stealing the air out of his lungs. Eren moaned, the sensations new, exhilerating and over-powering. 

Slowly he allowed the free hand, not supporting his weight, to skim down Eren's side; tracing every nook and cranny until he reached a protruding hip bone. His thumb skimmed along it, while his tongue was doing good at distracting Eren as it ran over the roof of Eren's mouth and the edges of his teeth. Eren sucked the slick muscle, quickly catching on and fighting for his share of dominance. Levi smiled against his lips,  _got you._

Eren jerked, back arching and tremors running through his body. His eyes started to blur, white lights flashing behind his eye lids and his head spinning with the loss of sense and white, hot pleasure which coursed through his veins. Levi's grip was firm and skilled, fingers flexing deliciously around him. His mouth fell open, saliva slipping out when Levi moved to kiss his neck instead. He latched onto the sweet skin, sucking harshly and grinding his teeth against it to add to the intensity. Over and over his teeth dug into the flushed skin, marking an oblivious Eren with a trail of love bites. 

His hand paused, Eren groaning immediately. He placed a wet, open mouthed kiss against Eren's navel, his chest brushing teasingly against the brunette's length. 

"L-Levi!" He croaked.

"Have you ever been sucked off, Eren?" 

Eren shook his head wildely, even though Levi already knew the answer. He twitched as he anxiously watched Levi's head move in between his shivering thighs.

 

"Nn-gah!" Eren covered his mouth, trying to keep his voice down when Levi's tongue grazed him.

 

"I hope you still think you're gay and suddenly approve of incest." Levi commented with a teasing chuckle.

 

He cried out when Levi's hot mouth enveloped his throbbing heat, blunt nails slicing into the pale skin of Levi's shoulders. Levi covered Eren's mouth with his hand, trying to muffle the lewd sounds. If he was turned on before... now he was ready to over-heat and combust at the tempting sight and sweet noises. His head moved up and down, wondering if he was doing it right since he had never given anyone a blowjob before. Eren's mewls were a pretty good indication. 

 

When he pulled away, he cringed at the disgusting mess of precum and saliva; pushing the thought away and focusing on Eren shortly after his inner struggle and fit about his OCD. Eren's body shook violently, seeking relieve as in yesterday. Levi pushed his sleeping bottoms down, followed by Eren's. 

 

"Ahh-ngh..kuh!" 

 

Levi had to swallow the shouted pleas and begs when his naked hips rocked against Eren's, slamming against him without a shred of mercy.

~


	2. Oh, brother.

**Notes for the Chapter:**

> So I'm going to post a smutty alternative ending x.x Their personalities might be different & I struggled writing this chapter butttt...meh. 
> 
> Again...smutty...and a bit lewd & twisted I suppose. (Just like us fans. :p) 
> 
> Enjoy it anyway xD

\--

" _You_  are not gay, Eren." Levi said in between chortles.

"And why the hell do you decide that?"

Levi stopped laughing, serious in a split second. His movements were too fast and Eren was pinned before he knew it, Levi's strong thighs hugging his and his face so close their noses brushed.

"Cause you freaked out about your brother's dick."

Levi's cool breath ghosted over Eren's blushing face and he stammered, shaking his head. Levi scoffed, shaking his as well before shifting to get off. Eren grabbed the back of his neck, yanking him back with a dizzying force. The boy was clumsy, his lips uncertain as they moved and completely off pace. Levi pushed against his shoulder, breaking away and keeping Eren against the pillow. Eren eyed him with gleaming eyes, breathing heavily and expecting him to yell and hit him for being so twisted. All Levi did was tease him but Eren just had to fuck it all up.

"If you want to kiss someone, fucking know how to do it." His voice was low, threatening and almost came out like a hiss.

Eren gaped like a fish, opening and closing his mouth without actually saying anything out loud. Levi’s hand slowly made its way to Eren’s neck, fingers gently winding around the base. His thumb stroked the flushed skin, enjoying the smooth texture mixing with the rapidly forming goose-bumps. Eren has always been so sensitive and responsive to physical contact. Levi’s head tilted to the side, his jaw brushing his shoulder and his raven hair falling over his narrowed eyes. The silvery-blue orbs burned holes into Eren’s stormy pools of aqua. 

“I-I’m sorry.” Eren mumbled softly.

Levi’s mouth twitched and his teeth showed for a split second, giving a cheeky smile.  Eren swallowed thickly, feeling his skin rub and his muscles contract against the palm of Levi’s hand. 

“This is…some creepy shit.” 

“Is it now?” 

“You gonna strangle me?”

“Perhaps. I think I’ve put up with enough little brother crap. Besides, you know my secret,” Levi made a thinking face, “How does that saying go again? If I tell you, I have to kill you?” 

“I always knew you were mental, asshole.” 

“Just like you, you little shit.” 

Both stared at each other for a painstakingly long minute. Levi’s eyes narrowed further and Eren chewed at the inside of his lip, heart drumming against his ribcage. Levi leaned closer, his body pressing further down against Eren and his thighs rubbing him in just the right way. 

“Shouldn’t joke about that shit. People might believe us.” Eren muttered suddenly, trying to look away. 

“I don’t particularly care.” Levi said with a bored tone, pausing. 

Eren just shook his head as best he could, licking his lip to clear the blood where his teeth cut into the flesh. 

“Pssst. Eren.”

Eren titled his head up, Levi’s nose brushing his before his lips pressed against Eren’s. His mouth opened with a silent gasp of surprise, Levi taking the opportunity to nip at his lip and pull it into his own mouth. His teeth held it for a moment before releasing and his tongue slithering out instead. Slowly it ran over the slick flesh, tasting the copper before going further and slipping into Eren’s mouth. Eren tensed, a hand shooting out to grab hold of Levi’s hair and his head tilting back. Levi smiled against his mouth, allowing his tongue to penetrate deeper and sucking the air out of Eren’s lungs. Eren opened his mouth wider, sucking in gulps of air and trying to get more of Levi’s kiss. Levi obeyed when he felt the insistent tug at the back of his. 

His mouth all but crushed Eren’s when he pushed down, teeth gnashing and tongues tangling. Eren moaned in the back of his throat, Arms winding around Levi’s shoulders and fingers running through the shorter hair of his buzz cut, enjoying the prickly and soft feel of it between his fingers. Levi’s hand moved higher, holding Eren’s jaw and tugging it to kiss him even harder and deeper. Eren moved a leg, the top of his thigh just brushing against Levi and making him pause and shudder. The almost unnoticeable moment of Levi’s hesitance Eren did not miss and he revelled in it; being able to stir the stoic Levi. Levi’s fingers skimmed along Eren’s bare side, digging softly into his hips as a way to restrain him or something. 

And then he pulled away. 

“That…was better.” Levi commented softly.

Eren stared up at him with wide eyes and swollen lips, breathing ragged and uneven. He smiled at the teen, pulling away and untangling him from Eren. Eren was quick to sit up, confused as to why Levi stopped.

“I think you should go to bed now, Mr ‘I found out I’m gay.’” Something  about his tone was off.

 Levi sat on the side of the bed, shifting his pyjama-bottoms before getting up and stretching. Eren did his best to ignore the cheesy rippling muscles across his back and shoulders, struggling out of the sheets to grab Levi’s wrist. 

“Wait, aniki!” 

“Thought you weren’t going to call me that anymore.” 

“Levi, where are you going?”  Eren ignored him, keeping his fingers tightly together around Levi’s wrist.

“I’m getting a drink and you’re getting to bed. _Your_ bed.”

“No.” Eren insisted. 

“Listen, enough is enough now. You don’t want to do this.”  Levi scoffed, looking at his feet with furrowed brows.

“Why? I think I’m being clear about it.” 

Eren tugged him back, standing with his knees digging into the matrass as he wrapped his arms around Levi’s shoulders, his chest pressing against Levi’s upper back. He opted to press the rest of his body just as close after a few silent seconds. Levi tensed visibly, shoulders rigid and neck straining. Eren leaned forward, kissing Levi’s right shoulder and then his neck, followed by his ear. Levi gave a tiny, almost inaudible protest and Eren struggled to keep his hips still. He tested him, rolling his neck to the side to give his little brother better access. Eren hesitantly racked his teeth across his skin, scraping at the sensitive skin beneath Levi’s ear and the side of his neck. 

Levi almost wanted to laugh at Eren for being so forward and incredibly stupid. 

He twisted around, catching Eren off guard. One hand held the back of Eren’s head, yanking him forward to catch his mouth in a messy kiss. The other grabbed a tanned hip, grinding his straining pants against Eren’s own. Eren loudly protested, shuddering and pushing away, covering his mouth with the back of his hand, the other pressing against Levi’s chest. 

“What? Didn’t expect it to feel like that? Have you ever had someone’s dick-” 

 Eren covered Levi’s mouth instead and looked away blushing. 

“God, do you have to be so bloody crude!”

“Hmm, can’t take dirty talk?”  

“Shut up.” Eren insisted. 

“So you changed your mind then?”

Eren blinked, staring hard at nothing in particular. Levi already knew the little brat won’t stand down and to prove his point, Eren kissed him again. And he wasn’t gentle at all. 

The raven-head pushed him backwards, following closely as Eren’s back hit the bed and Levi fell on top. Eren’s legs opened and wrapped around Levi’s waist, eyes blurring as he moaned into his brother’s mouth. Levi’s left hand cupped his behind, while his right kept him from crushing Eren beneath him. He rubbed slow circles through the thin fabric of his blue pyjamas, taking a liking to how Eren enjoyed the fabric against his skin. He squeezed it, Eren holding on tighter in response and he chuckled. His fingers trailed lower, sliding down Eren’s thigh and back up again. He repeated the action a few times, making sure to move slowly and irritate Eren. 

Eren protested, prompting Levi to go on and he was happy to oblige. His fingers skimmed up the front on Eren’s thigh this time, spreading his fingers wide and kneading the flesh beneath his cool palm. His fingers curled around the waistband, slowly pulling it halfway down and over Eren’s lean hips. Eren shook his head, muttering into Levi’s mouth.

“I can’t take it off if you don’t let go of me.” Levi scolded. 

“R-right.” Eren remembered, straightening his legs. 

Levi kissed his chin before moving to his jaw, brushing his lips against the slightly rough skin where Eren started to shave. He stood on his knees, still leaning over to scatter Eren with soft and wet kisses. He raked his teeth over a protruding collar bone, stopping to suckle softly and leave a screaming red mark. Next, was a pert nipple. He kissed both, running his tongue around it and closing his mouth around it for a moment. Abdominals shifted beneath his mouth, tensing and relaxing. He bit into Eren’s hip, securely holding onto him when his hips jerked.

“Nng! D-don-” 

Eren didn’t finish his sentence, biting into his hand to keep him from making too much noise. 

Levi lapped at the small wound running his lip against the V-line leading towards the inside of Eren’s thigh. He prompted Eren to lift his hips, slowly pulling the fabric off and kissing the line of his leg until he reached an ankle. Levi pulled his feet through, following the other leg up this time and peppering it with kisses as well. He ignored Eren’s throbbing problem and kissed his navel, still feeling it rubbing against his skin. 

"L-Levi!" He croaked.

"Have you ever been sucked off, Eren?"

Eren shook his head wildly, even though Levi already knew the answer. He twitched as he anxiously watched Levi's head move in between his shivering thighs.

"Nn-gah!" Eren covered his mouth, trying to keep his voice down when Levi's tongue grazed him.

"I hope you still think you're gay and suddenly approve of incest." Levi commented with a teasing chuckle.

He cried out when Levi's hot mouth enveloped his throbbing heat, blunt nails slicing into the pale skin of Levi's shoulders. Levi covered Eren's mouth with his hand, trying to muffle the lewd sounds. If he was turned on before... now he was ready to over-heat and combust at the tempting sight and sweet noises. His head moved up and down, wondering if he was doing it right since he had never given anyone a blowjob before. Eren's mewls were a pretty good indication. When he pulled away, he cringed at the disgusting mess of pre-cum and saliva; pushing the thought away and focusing on Eren shortly after his inner struggle and fit about his OCD. Eren's body shook violently, seeking relieve as in yesterday.

“You know, I can’t actually fuck you,” Levi mused sitting back on his haunches. 

Eren growled, pushing himself up with shaky arms, “You’re gonna have to, asshole, especially after all this.” 

Eren heaved; the room spinning from lack of oxygen but still managed to glare at Levi, “Or do you prefer to bottom?”

“Dominating is more my style.” Levi studied Eren. 

Eren fell back against the pillows, arms spread across them and elbows aligned with his head. His legs fell open, embarrassment already out the door. 

 “Then dominate me.” So fucking cheesy.

Levi licked his suddenly dry lips, swallowing and almost coming in his pants right then and there. He sat back, pulling his pants off and sighing with relieve when his swollen cock sprang free. Eren bit his lips, blushing and twitching eagerly. Levi crawled over him, holding his hand out to Eren. 

“Come on, lick them.” Levi said gently.

He hesitated before catching on and opening his mouth. His tongue ran over three digits, thoroughly wetting them with saliva. Levi pulled his hand away, kissing him softly as his hand trailed down Eren’s side and across his ass. His fingers slipped in between, tracing Eren’s entrance and murmuring something to him so he could relax. A single finger slipped pass the ring of muscle and Eren called out, eyes screwing shut. 

“Gah!”

“That’s one. Count with me, Eren.” Levi kissed his cheek. 

Slowly he moved in and out, loosening him up enough so he could add a second. 

“Eren.”

“T-two-mh!” 

Levi didn’t complain when Eren tugged too roughly at his hair, understanding his reactions.  He kissed the other cheek, moving to his neck as his fingers worked. He searched, feeling around the soft cavern for the little ball of nerves. When his fingers brushed something and Eren jerked, he knew he found what he was looking for. 

“T-there! Do that a-again-hah!” 

Eren’s hips moved against Levi’s fingers, pleasure overpowering the pain when Levi found his prostate. Eren jerked each time he stroked it, muttering senseless pleas as Levi slipped in a third finger.

“T-threhh!” Eren grew louder. 

“Does it hurt?”

Eren shook his head, fingers digging into Levi’s skull. 

“Then, you ready?” 

With a confirming nod, Levi pulled his fingers out. He rubbed the rest of the saliva over his thick length before aligning himself with Eren. 

“I don’t h-ave to…?”

“Pre-cum is enough.” Levi assured him. 

“Levi?” 

“Yes.”

Eren watched him with wide eyes and shook his head, “Nevermind.”

“I’ll go slow.” 

He kissed Eren’s forehead.

“Eren?” He nodded, “Put your head on my shoulder. Bite as hard as you want to if it hurts too much.”

Eren did as he was told, bracing himself when he felt the soft nudge at his behind. Before actually registering it, Levi was already halfway in and his teeth chomped down. Levi cursed and Eren groaned against his skin, teeth grinding into it. He stopped when he was fully sheathed, shuddering and arms shaking. The warm heat swallowed him deeper and clenched around him; he wasn’t lasting for much longer.

“G-Go.” 

Levi nodded. His body slowly moved, pulling out of Eren and then going back in. His ragged breath blew over Eren’s hair, ruffling it. Eren held him tighter, tongue now running over the bloody bite mark. Levi thrust harder, hitting Eren’s prostate and sending his body into a fit of convulsions. 

“Ah! S-hit!” 

Eren’s head thrashed from side to side. Levi kept on going, pounding into him over and over, feeling his climax so close. Eren’s nails dug into Levi’s skin; cutting into his back and hips as he held on and called out. The pleasure was something masturbation could not compare to. Levi panted, as he took hold of Eren’s leaking member, pumping it.  He cover Eren’s mouth with his, swallowing the screams as Eren’s spine arched and he reached his climax. With the constricting muscles closing around him, he was overwhelmed and came as well, filling Eren to the brim. 

\--

Levi breathed heavily, rubbing Eren’s hair out of his face and pulling him close. 

“You okay there?” 

“Yeah, that was fucking amazing.”  Eren sighed into his neck. 

“I can get arrested though.” Levi mused.

“I won’t tell!” Eren said seriously, hugging Levi tighter. 

“Sure, brat. Now go to sleep.”

“Levi?”

“What?”

“Can I skip school tomorrow and help you study instead or something?”

“Fine. I’ll make an exception this time.” 

\--

**Notes for the Chapter:**

> Happy?

**Author's Note:**

> Thank you for reading, darlings! :3


End file.
